Each of 15 students will give a 1 1/2 minute speech in english class. how long will it take to give the speeches

If each of the fifteen students in the class were to give their speeches exactly back to back with no gaps in between, then the speeches would take up 22.5 minutes of English class time. That is, the total allotment of time that students will spend speaking, whether or not there are gaps in between, is 22.5 minutes. You can find this solution by simply multiplying the number of students (15) by the amount of minutes that each will be speaking (1.5). If you have issues solving this without a calculator, know that multiplying by 1.5 means that your final answer will equal your original value (15) plus that original value halved (7.5, in this case). 15+7.5=22.5 Other ways to find this value include adding 1.5 to itself 15 times, which is the same thing as multiplying it by 15 but might make some students more confident that they've approached the problem the right way. Still another way to solve it is to convert 1.5 minutes to 90 seconds and to thus multiply 15 by 90 to see that it would take 1,350 seconds for the students to give their speeches. Divide that by 60 to convert back to minutes, and you see that it takes 22.5 minutes for the speeches to be given. Dividing by 60 again would tell you that it will take 0.375 hours to make these speeches, but minutes seems the more useful measurement under the circumstances.

The answer would be 13.5 minutes.